Freewheel hub with coaster brake and brake-locking device



May26, 1936. F. WINKLER Filed June 13, 1935 FREEWHEEL HUB-WITH COASTERBRAKE AND BRAKE LOCKING DEVICE Inventor Patented May 26, 1936 PATENTOFFIC FREEWHEEL HUB WITH COASTER BRAKE AND BRAKE-LOCKING DEVICE FranzWinkler, Schweinfurt, Germany Application June 18, 1935, Serial No.26,347 In Germany June 16, 1934 Claims.

The invention relates to a device for fixing the brake of a free-wheelcoaster brake particularly of bicycle hubs in its operative positionmerely by back-pedalling. In free-wheel coaster hubs in 5 which thedriving body is automatically coupled to the driving wheel on pedallingforward, while the application of the brake is effected bybackpedalling, whereby power is transmitted from the driver to thebrake, back pressure must be applied to the cranks continuously tomaintain the braking effect.

The object of the invention is to obtain immobilization of the driver onback-pedalling thus maintaining the brake applied for the desired timewithout requiring constant pressure being put on the cranks.

This object is attained by means of a frictionally engaging devicecomposed of substantially coaxial stationary parts and parts rotatingwith, and attached to, the driver; the device being mounted on the freeend of the driver and on the wheel axle, respectively. By soconstructing this locking device that the several parts come tofrictional engagement on back-pedalling automatic immobilization of thedriver and consequently continuous application of the brake will besecured, special means enabling disengagement of the frictional couplinggrip.

A further object of the invention is to allow further backward rotationof the driver after es tablishment of the locking effect, so that thebrake can be applied with increased power. This effect is attained byproviding frictional interengagement of some of the intermediatetransmitting parts of the device which parts permit a relative slidingrotation in spite of the engagement of the locking means.

In the accompanying drawing, which forms a part of this specification,two embodiments of the invention are represented by way of example. Inthe drawing Fig. 1 shows a side view of a bicycle coaster hub providedwith the locking device which is repre- Inthe embodiment of theinvention shown by Figs. 1 and 2, the usual lock nut for the sprocketwheel b on the driver a has been replaced by an intermediate disc swhich is, likewise screwed on the left-hand screw thread formed on thefree end of the driver and carries an annular lateral projection orflange g in a recess of which is lodged the end bent off outwards of anannular lock spring h. The free end of this look spring is provided witha plurality of small teeth directed towards the inside and adapted toengage with the corresponding teeth of a lock sleeve 2'. The bore of thesaid lock sleeve has a radial recess into which extends a lug k directedoutwards from a friction spring 1 which in turn is carried by a lateralcylindrical projection m1 of a nut m; said nut is adapted to be screwedwith a left-hand thread on the bearing come it stationarily fixed on thewheel axle d, and being taken along by friction by the spring I when thelatter revolves. Stops care provided by the ends of a recess made in theright hand vfaceof the nut which stops will permit of a limited rockingrotation of the said nut at the end of which one of the stops will bearagainst a lock finger 11. carried by a ring clamped on the wheel axle dbetween the cone u and a protecting cap :c. Thus on backward rotation ofthe nut m the friction ring Z is non-rotatably fixed while forwardrotation of the said nut will release the ring I.

The locking device operates as follows. When, by back-pedalling, thebrake (not shown) is actuated, the intermediate disc s will take alongthe lock spring h, and as the teeth at the free end thereof are inengagement with the teeth of the lock sleeve i the latter will be turnedin the same direction the same as 'the friction spring I which is by thelug is prevented from an angular displacement relatively to the saidsleeve 2. By the frictional contact, the friction spring 1 further takesalong the nut m which is thus screwed upon the left-hand thread of thecone it towards a shoulder thereof until the said friction spring hasbeen clamped against any angular displacement between this shoulder andthe nut m. On account of the positive interconnection above described ofthe several members also the lock sleeve i has now been immobilizedagainst any angular displacement. This locking effect is arrived at evenwhen braking starts. An increased braking effect being desired, itsuffices again to move the pedals slightly backwards so that the lockspring h is with its teeth shifted over the toothed periphery of thelock sleeve 2'. In this way it is possible to lock the driver in severalangular positions. When the brake is to be released the cyclist pedalsas usually forwards. This being done the lock spring h is put undertension around the periphery. of the lock sleeve i so that theinterlocking teeth are prevented from being disengaged. The lock sleevenow being turned in forward direction takes along the friction spring Iwhich turns the ring nut m by friction thereby screwing it in righthanddirection until the rear stop 0 has been brought into engagement withthe lock finger 12,

when the ring I will be free from being clamped.

Then the .driver is rendered freely revoluble again and the brake isbrought into its neutral position in the usual manner. The angulardisplacement of the nut m being limited is an important feature whichpermits of a small displacement of the pedals when the brake isactuated, so that the spring Z is clamped already when braking starts.

Referring to the embodiment shown by Figs. 3 and. 4, in the annularprojection g of the intermediate disc 3 there is yieldingly lodged asplit spring ring hi the ends of which leave a gap between them intowhich extends the projection k1 of a friction spring Z1. The othermembers are identical with those described above. Also the modusoperandi is substantially identical; when the brake is to be moretightened after havingbeen applied, the spring in prevented fromrelative angular displacement by the clamped friction spring 11 willslide with its periphery on the internal face of the projecting flange gwhich is being turned backwards for increasing the braking pressure.Continuous braking is effected by the driver being immobilized throughthe friction prevailing between the members g and hl. When the pedalsare moved in the forward direction this friction will suffice forreleasing the friction spring 11 again from its clamping position.

This embodiment also shows that for facilitating mounting the bearingcone may be made of two parts u and a1 coupled by means of teethprovided on their adjacent ends.

bers revoluble with the driver, stationary clamping means adapted tocouple said members to non-rotatable parts of the hub, and stopslimiting the stroke of the clamping means.

3. In a free-wheel coaster hub; the combination with a driver adapted toapply the brake on back-pedalling, of means rotatable with the driver, aspring member in engagement there-.

with, stationary clamping means having screw threads, a stop flange, anut screwable thereon towards and away from said stop-flange, andinterconnecting means disposed between the said spring members andclamping means and adapted to be immobilized by the clamping means.

4. In a free-wheel coaster hub, the combination with a driver adapted toapply the brake on back-pedalling, of a clamping coupling disposed uponthe wheel axle, a friction spring capable of being locked by theclamping coupling, stops for limiting the shifting movement of theclamping coupling, and means disposed between the driver and thefriction spring allowing a relative angular movement between them.

5. In a free-wheel coaster hub, the combination with a driver adapted toapply the brake on back-pedalling, of a clamping coupling disposed uponthe wheel axle, a friction spring capable of being locked by theclamping coupling, stops for limiting the shifting movement of theclamping coupling, and means disposed between the driver and thefriction spring, capable of sliding relative angular movement forbackward rotation of the driver during engagement of the clampingcoupling.

FRANZ WINKLER.

